The present invention relates to a conveyor system for transporting articles along a continuous conveyor path. More specifically, the present invention relates to a conveyor system that includes a plurality of articulated carriage roller assemblies that each travel between a pair of spaced tubular guide rails and maintain a carriage at a constant horizontal orientation as the carriage roller assembly travels along the conveyor path.
It is known to utilize material handling systems that incorporate endless members, such as chains or cables, that include a plurality of individual carriages that have platforms to support articles being moved by the conveyor system. In these type of material handling systems, a support platform of each individual carriage is held at a constant horizontal orientation to prevent the articles being supported by the carriage from falling off of the platform as the carriage is moved along both horizontal and vertical portions of the conveyor path.
Many prior art conveyor systems, such as shown in U.S. Pat. Nos. 5,207,314 and 2,608,28, include spaced roller tracks that engage rollers mounted on the carriage to guide the carriage and maintain its horizontal orientation as the carriage is transferred from a first horizontal path to a second horizontal path. In each of these above-identified patents, the roller tracks must be precisely positioned in order to ensure that the carriage platform remains at the desired horizontal orientation.
An additional problem associated with the conveyor system identified above is that each time the path of the conveyor changes direction, a roller guide track is required to ensure that the carriage platform remains in the desired, horizontal position as the direction of movement changes. In many of the prior art conveyor systems identified above, the carriage also requires a pair of roller guide tracks whenever the carriage is traveling over a path other than horizontal.
Therefore, it is an object of the present invention to provide a conveyor system that includes a plurality of individual articulated carriage assemblies that travel along the conveyor path and support the carriage at a constant horizontal orientation. It is a further object of the present invention to provide a conveyor system that includes a driven conveyor chain that is coupled to each of the individual carriage roller assemblies by a center shaft such that the orientation of the carriage mounted to the center shaft remains horizontal. Further, it is an object of the present invention to provide a conveyor system that includes a pair of tubular guide rails that defines an endless conveyor path along which the plurality of carriage roller assemblies travel.
The present invention relates to a conveyor system for transporting articles that are supported by a carriage along an endless conveyor path. Each of the carriages moving along the endless conveyor path includes a support platform that maintains a constant horizontal orientation as the carriage moves along the conveyor path. The conveyor path may include separate sections that each extend either vertically or horizontally and are joined by curved comer sections.
The conveyor system includes a plurality of individual carriage roller assemblies that travel between a pair of spaced guide rails that define the endless conveyor path. The conveyor path is defined by an inner tubular guide rail and an outer tubular guide rail that are parallel to each other and are spaced by a constant distance over the entire conveyor path.
Each of the carriage roller assemblies is positioned within the space between the inner and outer tubular guide rails. Each carriage roller assembly includes an articulated body that has a plurality of front guide rollers and a plurality of back guide rollers. A pair of the front guide rollers and a pair of the back guide rollers contact the inner tubular guide rail. A second pair of the front guide rollers and a second pair of the back guide rollers contact the outer tubular guide rail such that the front and back guide rollers support the carriage roller assembly along the inner and outer tubular guide rails as the carriage roller assembly moves along the endless conveyor path.
The articulated carriage body is jointed to allow the plurality of front guide rollers to move relative to the back guide rollers. The articulated carriage body allows the carriage roller assembly to travel around the curved comer sections of the endless conveyor path between sections of the endless conveyor path that extend in different directions.
The carriage roller assembly includes a center shaft about which the front and rear guide rollers are independently pivotable. The center shaft extends through the carriage body and is attached to a support bar of the carriage. The support bar, in turn, is connected to the platform of the carriage that is used to support the articles being transported by the conveyor system. The support bar of the carriage is securely fixed to the center shaft such that when the center shaft rotates, the support bar of the carriage rotates along with the center shaft.
The end of the center shaft opposite the carriage passes through a carriage chain. A drive assembly drives the carriage chain such that the interconnection between the carriage chain and the center shaft for each carriage roller assembly moves the carriage roller assembly along the endless conveyor path. The center shaft is rotatable relative to the carriage chain such that the orientation of the carriage mounted to the center shaft can change relative to the conveyor chain and carriage body.
The center shaft of each carriage roller assembly is connected to a leveling chain by a coupling arm. The leveling chain extends along the length of the endless conveyor path and is positioned relative to the conveyor chain such that the coupling arm maintains a constant orientation over the entire length of the conveyor path. In the preferred embodiment of the invention, the coupling arm remains vertical along the entire length of the conveyor path such that the platform of the carriage remains generally horizontal to support an article along the entire conveyor path.
A common drive assembly drives the leveling chain and the conveyor chain. Both the conveyor chain and the leveling chain pass around respective guide sprockets that maintain the desired relationship between the leveling chain and the conveyor chain.